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Route Constraints

A couple of interesting (in a HS2-interesting sort of way) videos have caught my attention recently.

The first is from a BBC report about the HS2 summit organised by Bucks CC in April. In the second part of the report, they have an interview with Hugh Jaeger from Thames Valley Rail Future. He is opposed to the HS2 proposal on the grounds that is the wrong route at the wrong speed.

In particular, he says that the then Labour Government insisted that the route should go through Old Oak Common to provide a link to Heathrow: Hugh says that this doubles the amount of tunnel and adds £1 billion to the cost, even though only 1.4% of HS2 passengers would be going to Heathrow.

The second video is from a talk given by Christian Wolmar to the Chiltern Society and posted on his website.

He also talks about the route of HS2: in this case he points out that the HS2 analysis shows a huge business case for stopping at Milton Keynes. However, he says, this was the wrong answer for HS2 Ltd: they didn’t want it to stop there, so came up with some sleight-of-hand reasoning to change the route.

But there is another major criticism of the way the route is planned. Many people in favour of high speed rail talk about how HS2 could be part of the continental high speed rail network. To do this it has to join up with HS1. But when HS2 Ltd were coming up with the design for the route of HS2, they did not include this link in their original plans, almost as if they had forgotten it.

So when looking at HS2 Consultation Question 4, maybe it’s worth asking why HS2 Ltd constrained the route like this? – to exclude a station which many thousands of people would use every day and add in a station used by a very small percentage of passengers? And why ignore the very obvious need for a connection to HS1.

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As for Christian Wolmar, I have to say he goes down further in my estimation every time he opens his mouth. For a self-appointed railway expert, he seems to have very sparse knowledge of how railways actually operate.

High speed lines work best like a pipeline, when all the trains on them are running non-stop at the same speed.

The HS2 plan sees up to 18 trains per hour operating on the route between London and the West Midlands once the “Y” network is built. Let us imagine there is a station at Milton Keynes as he suggests (ignoring for the moment that the HS2 route doesn’t go through MK). The times of heaviest demand from MK are in the morning and evening peaks. That is also the time of heaviest demand on the long distance trains. MK commuters would stand to benefit by about 10 minutes if a long-distance HS train were to be stopped there, whilst everybody already on the train would be penalised by about 8 minutes, because of the time lost in braking + station dwell + acceleration. So the MK commuters would need to outnumber the existing passengers by 5:4 just to break even in journey times (which means either the long distance train would need to be running half empty from its point of origin – unlikely in the peak period – or there would be a lot of uncomfortable overcrowding on the train).

Then let us consider the effect on route capacity of making an intermediate station stop in the middle of a high speed route. You don’t do this instantaneously, it takes time to slow down and time to accelerate again. So instead of consuming 1 non-stop train path, your stopping train will consume at least 2 and maybe 3. On a route that is full (as 18 trains per hour would be) that would mean CANCELLING 2 or 3 long-distance trains in order to insert a single stop at Milton Keynes. Does it make sense to cancel a train from (say) Leeds in the morning peak so that MK commuter can save 10 minutes? Emphatically no.

Wolmar’s failure to demonstrate any understanding of the basics of railway timetabling, capacity and operations undermine his entire credibility on the subject of HS2.

On a route designed for 300 kph the curvature can be sharper than one designed for 400 kph. However that is not the point being made in the interview. He was saying it would cost significantly more to build it for 400 kph than for 300 kph, and I do not believe this to be the case. Incremental cost from 200 kph to 400 kph is less than 10% according to HS2 (i.e. the difference between building a conventional railway and an HS railway).

An interesting interview with Mr Jaeger, but he seems to have got so much of it badly wrong.

The only available surface rail route out of London towards Birmingham and the North West is the former Great Western / Great Central Joint Line from Old Oak Common via Northolt and Ruislip. Alternatives such as following the M1 out of London would be massively more destructive to people and the environment than the HS2 proposals. Therefore they would have to go in tunnel instead. So it is Mr Jaeger’s alternative that would massively increase tunnelling, not the HS2 proposals as he claims.

I believe Heathrow is a complete distraction to the HS2 project. It is a waste of time and money sending the line there. People want to go to / from London, not Heathrow, so why delay trains, reduce capacity, and increase costs by serving Heathrow? On that I agree with Mr Jaeger.

That said, I think Old Oak Common station has many benefits as a West London interchange station in its own right regardless of anything to do with Heathrow. Connecting with Crossrail and Great Western Main Line is far more important.

As for costs of designing and building the route for 400 kph versus 300 kph, the only difference would be in tunnels if you wanted to maintain 400 kph you would need a bigger tunnel diameter. HS2 is only 400 kph in north of the Chiltern Tunnel in any case, so I think he(Mr Jaeger) has got his facts wrong there as well.

At first glance, the website appears to be advocating rail travel all over……..but once you delve into it, you realise that a lot of contributors are actually either current or ex rail employees, who are probably one of the most argumentative group of people on the web.!!

Whilst I was doing some research a few weeks ago, I came across one of their ” blogs ” …..a bunch of them were arguing about the definition of a ” train conductor ” ( I kid you not !! ). One of the posters spat his dummy out , posted a load of expletives, and promptly got himself banned from the site !!